RPMGroups

Valid RPM GROUPS

Fedora 25 lists them in /usr/share/doc/rpm/GROUPS (unchanged at least since Red Hat 9):

Amusements/Games
Amusements/Graphics
Applications/Archiving
Applications/Communications
Applications/Databases
Applications/Editors
Applications/Emulators
Applications/Engineering
Applications/File
Applications/Internet
Applications/Multimedia
Applications/Productivity
Applications/Publishing
Applications/System
Applications/Text
Development/Debuggers
Development/Languages
Development/Libraries
Development/System
Development/Tools
Documentation
System Environment/Base
System Environment/Daemons
System Environment/Kernel
System Environment/Libraries
System Environment/Shells
User Interface/Desktops
User Interface/X
User Interface/X Hardware Support

In common use is another group that is not part of the "official list". It exists as a sort of non-group group:

Unspecified

A useful command to show what groups are being used by a set of packages:

rpm -qa --qf '%{group}\n' | sort -u

Here's a variation useful to package developers seeking examples for each group. It lists every package installed on a system, sorted by RPM Group:

rpm -qa --qf '%{group} %{name}\n' | sort -u

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